Having gotten tired of all the rain in Kristiansand over the last two days, today I decided to fly from ENCN to ENTO to visit family. Not that the weather was so much better in Sandefjord…
Departure TAF was 9999 -SHRA SCT015 BKN030 and TEMPO 3000 RA BKN008 SCT020CB. The radar image did not however indicate any CBs.
Destination was 9999 -SHRA FEW006 BKN020 TEMPO 1000 RA BCFG BKN004 SCT015CB
The last METAR before departure made me expect landing on RWY36. I had a decent alternate in ENRY.
Upon departure from ENCN the weather was decent but I soon entered the clouds and remained there for the rest of the trip at 5000’. En route I did not observe any sign of CBs. When I managed to pick up the METAR for ENTO two thing were clear: there had been a change of runway, and the actual ceiling was lower than the TAF. I positioned for the ILS18 and was handed over to the tower who assured me that the lights were “on 100%”. I saw the approach lights just before the minima but they almost disappeared again before I finally acquired them and the rest of the runway environment.
So yes there are limits for GA flying. They are layed out in the legislation. I would not have done this flight had I not been reasonably current and had I not had a good alternate, in this case ENRY where the worst part of the TAF was 3000 RA BKN008. I also had 0 pressure to get there, I was by myself (no passenger to worry about) and it provided me with valuable training.
Patrick wrote:
Though I already listened to the ATIS again on the ground – I believe it was the next letter (i.e. either revised or just the next regular interval) and it was still 10 km or more.
It could also be that the prevailing visibility was 10 km (or more) and the visibility in your direction was 5 km. Variations in visibility don’t have to be reported if the lowest visibility is at least 5 km.
Also, there is a difference between flight visibility and (observed) meteorological visibility at ground level. Your flight visibility could well be 5 km and the meteorological visibility 10 km at the same time!
I think guys this 1.5km/3km is heavily country dependent.
Airborne_Again wrote:
You wrote that you were surprised (or so I understood) that the ATIS reported 10 km while the viz was actually 5 km. I know that observed figures have to change quite a bit from the previously reported ones before a special report is made
Correct. Though I already listened to the ATIS again on the ground – I believe it was the next letter (i.e. either revised or just the next regular interval) and it was still 10 km or more.
Peter wrote:
But then UK pre-JAR PPLs might have been 1500m too.
They were not. The 3000 m limitation was around before JAR-FCL.
Patrick wrote:
True, but with Special VFR that would again be 1500m.
Yes, but that’s not what I’m talking about.
You wrote that you were surprised (or so I understood) that the ATIS reported 10 km while the viz was actually 5 km. I know that observed figures have to change quite a bit from the previously reported ones before a special report is made. There are specific “gates” where a special report is required. I don’t have access to the criteria right now, but it seems reasonable to me that 5 km is such a “gate” as the VMC/IMC distinction is operationally significant. Indeed, as you point out, if viz drops below 5 km you need Special VFR for visual flight.
The discussion concerned Patrick’s flight into Cologne/Bonn. That is an airport with a control zone. Class D in Germany, if I am not mistaken. Thus the visibility limit for VMC is 5000 m.
True, but with Special VFR that would again be 1500m.
1500m is applicable for fixed wings, helicopters can go down to 800m. There was a time where also rule of speed/visibility ratio was valid /for 200kph (kph, not kts) the minumum was 2km/ but this is gone, max speed is now 140 kts. 1500m is crazy at 95kts, not speaking about 140kts ;-)
The main reason Germany (and presumably others) have always had those 1500m for VFR is to allow legal operation of helicopters.
1500m is really poor visibility. On an IAP, one can only just about see the runway at an MDH of 800ft. And VFR flight (fixed wing) is impossible in 1500m unless flying very low (well below 1000ft). Visual navigation is obviously impossible – you have to use GPS or know where you are anyway. Even 3000m cannot be visually navigated using traditional PPL methods, if flying at sensible altitudes.
That’s why it’s a minimum. Everybody is free to (and should) set his own minimums.
Many people misunderstand the idea of minimums and think that as long as they are above legal minumums., it must be safe to fly. No. It depends on the circumstances.
As such, minimums need to have, well, pretty low values. Take that 1500 metres visibility minimum. Immagine a pilot, at his local airfield that he knows very well, in his own aircraft that he also knows very well. The pilot needs to fly a few circuits (for whatever reason). Misty weather – skies clear, calm wind but only 2500 metres vis. But it would be illegal to fly if the minumum were say 3000 metres.
